Implantable medical devices, such as electrical stimulators, may be used in different therapeutic applications. In some therapy systems, an implantable electrical stimulator delivers electrical therapy to a target tissue site within a patient with the aid of one or more medical leads that include electrodes. In addition to or instead of electrical stimulation therapy, a medical device may deliver a therapeutic agent to a target tissue site within a patient with the aid of one or more fluid delivery elements, such as a catheter.
Implantable medical devices, such as electrical stimulators, may target, for example, neurological disorders that include movement disorders, such as tremor, Parkinson's disease, multiple sclerosis, or spasticity. Implantable medical devices may also monitor functions of the organs with which they are associated, such as, for example, the functions of the brain. Monitoring functions of the organs targeted by an implantable medical device may support delivery of more effective therapy stimulation. In some cases, particularly with neurological and brain-related disorders and functions, abnormalities may be difficult to detect and distinguish from normal functionalities.